In a radio communication system, a plurality of users, via User Equipment (UE), each wirelessly connect to various Base Transceiver Stations (BTSs) for communication. Examples of the radio communication system can include European Telecommunications Standards Institute Digital Mobile Radio (ETSI-DMR), Terrestrial Trunked Radio (TETRA), Project 25 (P25), Land Mobile Radio (LMR), and the like. In a group call, an originator places a call to members of an associated talk group. In operation, some of the members may miss the group call, but the originator still may need all the members to attend. Conventionally, the workaround to this problem, i.e., group members missing a group call, can include: i) making an acknowledged group call to know who is missing then making individual calls for all the missing members, or ii) involving a dispatcher to make a dynamic group call. There are disadvantages with both of these approaches. With the acknowledged group call, it is inefficient to poll every member, especially when the members are apart and communicating with different BTSs and there is a large number of members in the group, and it is inefficient and impractical for the originator to make a subsequent subgroup call only with missed group members. With involving the dispatcher, a third-party has to be involved and there is pre-configuration required for a dynamic group call.
Accordingly, there is a need for an improved method and apparatus for a subgroup call to group members missing a group call.
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The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.